1. Field of the Invention
The present invention relates to a rotary forming machine and to a rotary tool utilized therewith to form a workpiece.
2. Description of the Prior Art
One type of conventional forming machine incorporates a pair of reciprocal gear racks having teeth that oppose each other as the racks are reciprocated into an opposed relationship on opposite sides of a workpiece. Engagement of the teeth on the gear racks with the workpiece causes a forming operation to take place that forms the workpiece with the desired configuration. Machines of this type are disclosed by U.S. Pat. Nos. 3,214,951 and 3,793,866. Gear racks which may be utilized with this type of machine are disclosed by U.S. Pat. Nos. 2,994,237; 3,015,243; and 3,672,203.
Another type of forming machine utilizes rotary forming tools to form a workpiece. A pair of such tools are rotatably supported in a spaced relationship to each other. The periphery of these tools defines a forming face that engages the workpiece to provide the forming operation. U.S. Pat. No. 2,886,990 discloses one such forming machine in which substantially the total 360.degree. periphery of each rotary tool defines its forming face. Each of the tools also has a relieved area that allows loading and unloading of the workpiece to take place between the two tools of the machine. Each cycle of the machine is thus performed as the tools rotate one revolution about their respective axes. Another similar machine is disclosed by U.S. Pat. No. 3,201,964. The rotary tools of this machine each have a pair of forming faces on their periphery. Consequently, a complete forming operation is performed by a one-half revolution of the tools. Damage or wear to either of the forming faces on one of the tools requires replacement of the tool even though the other forming face is still usable. Another similar rotary forming machine is disclosed by U.S. Pat. No. 3,630,058.